1. Technical Field
Example embodiments relate generally to semiconductor devices, and more particularly to volatile memory devices and system-on-chips including the volatile memory devices.
2. Description of the Related Art
A volatile memory device should be continuously supplied with power to retain stored data. A voltage level of a power supply voltage supplied to the volatile memory device has been decreased to reduce power consumption. However, as the semiconductor process technology has been advanced, a distribution of characteristics of memory cells of the volatile memory device has widened. Accordingly, operation stability of the memory cells may not be ensured at the decreased power supply voltage.